Irrigation technology for climate change adaptation

Authors: Evett, Steven - Steve

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/18/2023
Publication Date: 10/18/2023
Citation: Evett, S.R. 2023. Irrigation technology for climate change adaptation [abstract]. International Annual Conference on Agriculture and Biotechnology (IACAB 2023), October 17-18, 2023, Samarkand, Uzbekistan. Virtual.

Interpretive Summary:

Technical Abstract: Climate change creates many challenges for crop production in irrigated settings in semi-arid and arid lands where one third of world population lives on 43% of cultivated land. Keys to adaptation can be found by examining the equations for calculating crop water productivity (CWP), which is the economic yield of a crop divided by the crop water consumption. Larger values of CWP indicate more crop obtained per drop of water used. The several factors in these equations can be manipulated to increase the CWP. These factors include irrigation amount (and timing), precipitation, evaporation losses, deep percolation and runoff losses, the harvest index, the crop transpiration, and the total dry matter production. Of these, reducing losses of water to evaporation is one of the more straightforward and effective means to increase CWP, and using subsurface drip irrigation is one of the most effective ways to reduce evaporative losses in irrigated agriculture. The role of agricultural science over the past 50 years in reducing use of water and other resources cannot be overstated. Total factor productivity has increased three-fold while overall resource use has remained flat. Improved irrigation application methods have meant that irrigated water use has declined by 24% since 1980 while total U.S. irrigated area remained the same. Precision irrigation practices are now coming to the fore, particularly with the advent of enabling technologies such as GPS, GIS, miniaturized computing power, data in the Cloud (internet), cellular networks for data transmission, the internet of things (IoT) and low-cost wireless sensor systems, and open-source hardware and software. All of these technologies enable precise control of pressurized irrigation systems so that water is applied in time and space as it is needed by plants for optimal productivity. The USDA ARS developed Irrigation Scheduling Supervisory Control And Data Acquisition (ISSCADA) system and its control software, ARSPivot, is an outstanding example of the merging of sensing and control technologies into a user-friendly decision support system for site specific variable rate center pivot irrigation system control. This system can be used on center pivot irrigation systems that are used on more than 55% of U.S. irrigated lands. The usefulness of such systems for water security, precision agriculture and sustainability in the face of climate change is clear and leads to several key considerations: Establishing water security is key to sustainability; In a water scarce nation, virtual water trading is immensely important; High value crops and other produce are key to establishing a positive virtual water trading context; Precision irrigation decreases the virtual water content of high value crops, and of products such as meat, eggs, and milk that are derived from crops; Precision irrigation cost can be justified by profitability of high value crops and products; and Establishment of precision irrigation manufacturing in-country is key.